NCERT Class 9 Science Chapter 2 | Is Matter Around Us Pure? | MCQ
Here are important multiple choice questions from CBSE Class 9 Science Chapter 2.
1. …………………….. are constituted by more than one kind of pure component.
a) mixtures
b) matter
c) atoms
d) substances
Answer: mixtures
2. A substance cannot be changed into other kinds of matter by any ………………………….. process.
a) chemical
b) physical
c) electrochemical
d) None of these
Answer: physical
3. Which of the following is an example of a pure substance?
a) sugar
b) milk
c) soil
d) Juice
Answer: sugar
4. A mixture contains …………………………… substance.
a) one
b) two
c) three
d) more than one
Answer: more than one
5. Mixtures that have a uniform composition throughout are called ……………………………
a) homogeneous mixtures
b) heterogeneous mixtures
c) indigenous mixtures
d) None of these
Answer: homogeneous mixtures
6. Mixtures which have non-uniform compositions and physically different parts are called …………………………
a) homogeneous mixtures
b) heterogeneous mixtures
c) indigenous mixtures
d) None of these
Answer: heterogeneous mixtures
7. Sugar dissolved in water is an example of a …………………………………..
a) homogeneous mixture
b) heterogeneous mixture
c) indigenous mixture
d) None of these
Answer: homogeneous mixture
8. A mixture of oil and water is an example of a ………………………………….
a) homogeneous mixture
b) heterogeneous mixture
c) immiscible solution
d) heterogeneous immiscible solution
Answer: heterogeneous immiscible solution
9. When you add chalk powder or wheat flour to water, you get a ……………………………..
a) solution
b) suspension
c) colloidal solution
d) None of these
Answer: suspension
10. When you add a few drops of milk or ink to water, you get a ………………………………..
a) solution
b) suspension
c) colloidal solution
d) All of the above
Answer: colloidal solution
11. ……………………….. is a pure single form of matter.
a) substance
b) solution
c) mixture
d) All of these
Answer: substance
12. A ………………………….. is a homogeneous mixture of two or more substances.
a) solution
b) colloidal solution
c) suspension
d) None of these
Answer: solution
13. Alloys are …………………………………
a) solid solutions
b) colloidal solutions
c) gaseous solutions
d) None of these
Answer: solid solutions
14. ………………………………. are mixtures of two or more metals and a metal or non-metal.
a) alloys
b) metalloids
c) semiconductors
d) None of these
Answer: alloys
15. Brass is an alloy of ……………………. and ………………………
a) silver and copper
b) copper and zinc
c) copper and iron
d) zinc and iron
Answer: copper and zinc
16. Name the components of a solution.
a) solvent and solute
b) solvent and catalyst
c) catalyst and solute
d) None of these
Answer: solvent and solute
17. The component that is dissolved in the solvent is the ………………………………
a) solute
b) solution
c) catalyst
d) None of these
Answer: solute
18. The component that dissolves the other component in a solution is the ………………………………..
a) solute
b) solution
c) solvent
d) catalyst
Answer: solvent
19. Tincture of iodine is a solution of …………………………….
a) iodine and alcohol
d) iodine and oil
c) iodine and water
d) iodine and spirit
Answer: iodine and alcohol
20. Name the solute and solvent in soda water
a) oxygen and water
b) water and carbon dioxide
c) carbon dioxide and water
d) carbon and water
Answer: carbon dioxide and water
21. Which is the main constituent of air?
a) oxygen
b) carbon
c) nitrogen
d) hydrogen
Answer: nitrogen
22. When no more solute can be dissolved in a solution at a given temperature, it is called a ………………………………
a) dilute solution
b) concentrated solution
c) saturated solution
d) None of these
Answer: saturated solution
23. The amount of solute present in the saturated solution at a given temperature is its ………………………………..
a) solvency
b) solubility
c) solvent
d) None of these
Answer: solubility
24. A solution contains 50 gram of common salt in 350 gram of water. Calculate the concentration in terms of mass by mass percentage of the solution.
a) 1.25%
b) 12.5%
c) 10%
d) 11.5%
Answer: 12.5% ((50/400) x 100 = 12.5%)
25. Non-homogeneous solutions in which solids are dispersed in liquids are called ……………………………
a) saturated solution
b) colloidal solution
c) suspension
d) non saturated solution
Answer: suspension
26. Particles of a ………………………….. are visible to the naked eye.
a) solution
b) suspension
c) saturated solution
d) None of these
Answer: suspension
27. A colloid is a ……………………………… mixture.
a) homogenous
b) heterogenous
c) Neither of these
Answer: heterogeneous
28. The scattering of a beam of light by a colloidal solution is called………………………….
a) Raman effect
b) Hawking effect
c) Tyndall effect
d) None of these
Answer: Tyndall effect
29. Which technique can be used to separate the particles of a colloidal solution?
a) filtration
b) boiling
c) evaporation
d) centrifugation
Answer: centrifugation
30. Which method is used to separate dye from ink?
a) filtration
b) evaporation
c) centrifugation
d) sieving
Answer: evaporation
31. Which method is used to separate cream from milk?
a) evaporation
b) centrifugation
c) filtration
d) None of these
Answer: centrifugation
32. Which method of separation is used in diagnostic laboratories for blood and urine tests?
a) centrifugation
b) filtration
c) handpicking
d) evaporation
Answer: centrifugation
33. When a liquid is spun rapidly, the denser particles are pushed to the bottom and the lighter particles stay at the top. This method of separation is called …………………………
a) centrifugation
b) filtration
c) handpicking
d) evaporation
Answer: centrifugation
34. When we add oil to water, they do not mix and form two separate layers. Such liquids are called
a) miscible liquids
b) immiscible liquids
c) saturated liquids
d) unsaturated liquids
Answer: immiscible liquids
35. Which of the following is an example of solids which sublime when kept in an open container?
a) camphor
b) sodium chloride
c) potassium permanganate
d) calcium carbonate
Answer: camphor
36. Pick the odd one out.
a) naphthalene
b) camphor
c) ammonium chloride
d) sodium bicarbonate
Answer: sodium bicarbonate (All the other three substances sublime.)
37. Which method is used to separate salt and ammonium chloride?
a) centrifugation
b) sublimation
c) filtration
d) None of these
Answer: sublimation
38. Which method is used to separate drugs from blood?
a) sublimation
b) chromatography
c) oxidation
d) filtration
Answer: chromatography
39. Which method is used to separate a mixture of two miscible liquids?
a) sublimation
b) distillation
c) centrifugation
d) None of these
Answer: distillation
40. Which method of separation is used for separating a mixture of two or more miscible liquids for which the difference in boiling points is less than 25K?
a) distillation
b) fractional distillation
c) sublimation
d) evaporation
Answer: fractional distillation
41. Which method is used to separate different gases from air?
a) distillation
b) fractional distillation
c) sublimation
d) evaporation
Answer: fractional distillation
42. Which method is used to purify solids?
a) distillation
b) fractional distillation
c) sublimation
d) crystallisation
Answer: crystallisation
43. Which method is used to separate a mixture containing kerosene and petrol which are miscible with each other?
a) distillation
b) fractional distillation
c) sublimation
d) evaporation
Answer: distillation
44. Name the technique used to separate camphor from salt?
a) distillation
b) fractional distillation
c) sublimation
d) evaporation
Answer: sublimation
45. What is the basic form of matter that cannot be broken down into simpler substances by chemical reactions?
a) compound
b) element
c) substance
d) None of these
Answer: element
46. Which is the only metal that exists in liquid form at room temperature?
a) argon
b) mercury
c) calcium
d) phosphorus
Answer: mercury
47. Which of the following is an example of a metalloid?
a) iodine
b) silicon
c) bromine
d) chlorine
Answer: silicon
48. Pick the odd one out.
a) boron
b) silicon
c) germanium
d) carbon
Answer: carbon (Carbon is a non-metal; the other three are metalloids.)
49. Name the two elements which are liquids at room temperature
a) boron and silicon
b) germanium and mercury
c) mercury and bromine
d) bromine and argon
Answer: mercury and bromine
50. The constituents of a compound can be separated only by ………………………….
a) physical changes
b) chemical changes
c) physical and chemical changes
d) chemical and electrochemical changes
Answer: chemical and electrochemical changes
51. When elements just mix together, they form …………………………………
a) a mixture
b) a compound
c) an alloy
d) a metalloid
Answer: mixture
52. When elements react with one another, they form …………………………..
a) mixtures
b) compounds
c) solutions
d) None of these
Answer: compounds
53. Which is a colourless gas that smells like rotten eggs?
a) hydrogen
b) carbon monoxide
c) hydrogen sulphide
d) bromine
Answer: hydrogen sulphide
54. Pure substances can be …………………………..
a) elements
b) compounds
c) mixtures
d) elements or compounds
Answer: elements or compounds
